1-(4&#39;-hydroquinonylalkylphenyl)-3-n-(hydroxylalkyl)-carbamyl-4-[(n, n-dialkylsulfonamido)-phenylazo]-5-pyrazolones



United States Patent 1 (4' HYDROQUINONYLALKYLPHENYL) 3 N (HYDROXYLALKYL) CARBAMYL 4 [(N,N-DI- ALKYLSULFONAMIDO) PHENYLAZO] 5 PY- RAZOLONES Milton Green, Newton Center, Mass, assignor to Polaroid Corporation, Cambridge, Mass., a corporation of Dela- Ware No Drawing. Filed Mar. 27, 1963, Ser. No. 268,451

7 Claims. (Cl. 260-463) This invention relates to photography and more particularly to products, compositions and processes for the development of photosensitive silver halide elements.

It is one object of the present invention to provide novel processes and compositions for the development of silver halide emulsions, in which colored developing agents are used to develop a latent image.

Another object is to provide novel processes and compositions for the development of silver halide emulsions, in which the novel developing agent is capable of developing a latent image and imparting a reversed or positive colored image of said latent image to a superposed imagereceiving material.

A further object is to provide novel products, processes and compositions suitable for use in preparing monochromatic and multichromatic photographic images.

Other objects of the invention will in part be obvious and will in part appear hereinafter.

The invention accordingly comprises the processes involving the several steps and the relation and order of one or more of such steps with respect to each of the others, and the products and compositions possessing the features, properties and the relation of elements which are exemplified in the following detailed disclosure, and the scope of the application of which will be indicated in the claims.

For a fuller understanding of the nature and objects of the invention, reference should be had to the follow-, ing detailed description.

The novel photographic developing agents employed in this invention possess the properties of both a dye and a developing agent; thus they may be referred to as dye developers. The nature of these dye developers will be described hereinafter.

The photographic processes and compositions disclosed herein are particularly useful in the treatment of an exposed silver halide emulsion, whereby a positive dye image may be imparted to another element, herein referred to as an image-carrying or image receiving element.

US. Patent 2,983,606, issued May 9, 1961 to Howard G. Rogers, discloses diffusion transfer processes wherein a photographic negative material, suchas a photographic element comprising an exposed silver halide emulsion is developed in the presence of a dye developer to impart to an image-receiving layer a reversed or positive dye exposed and wetted with a liquid processing composition, for example, by immersing, coating, spraying, flowing, etc., in the dark, and the photosensitive element superposed, prior to, during or after wetting, ou an imagereceiving element. In a preferred embodiment, the photosensitive element contains a layer of dye developer, and the liquid processing composition is applied to the photosensitive element in a uniform layer as the photosensitive element is brought into superposed position with an image-receiving element. The liquid processing composition permeates the emulsion to provide a solution of dye developer substantially uniformly distributed therein. As the exposed silver halide emulsion is developed, the oxidation product of the dye developer is immobilized or precipitated in situ with the developed silver, thereby providing an imagewise distribution of'unoxidized dye developer dissolved in the liquid processing composition. This immobilization is apparently, at least in part, due to a change in the solubility characteristics of the dye developer upon oxidation, and especially as regards its solubility in alkaline solutions. It also may be due, in part, to a tanning effect on the emulsion by the oxidized developing agent. At least part of this imagevvise distribution of unoxidized dye developer is transferred, by imbi'bition, to a superposed image-receiving layer. Under certain circumstances, the layer of the liquid processing composition may be utilized as the image-receiving layer. diffusion, from the emulsion, of unoxidized dye developer, without appreciably disturbing the imagewise distribution thereof, to provide a reversed or positive, colored image of the developed image. The image-receiving element may contain agents adapted to mordant or otherwise fix the diffused, unoxidized dye developer. If the color of the diffused dye developer is affected by changes in the pH of the image-receiving element, this pH may be adjusted in accordance with well-known techniques to provide a pH affording the desired color. Imbibition periods of approximately one minute have been found to give good" results, but this contact period may be adjusted where necessary to compensate for variations in temperature or other conditions. The desired positive image is revealed by stripping the image-receiving element from the photosensitive element at the end of the imhibition period.

The dye developers of this invention may be utilized in the photosensitive element, for example in, on or behind the silver halide emulsion, or they may be utilized in the image-receiving element or in the liquid processing composition. In a preferred embodiment, a coating or layer of the dye developer is placed behind the silver halide emulsion, i.e., on the side of the emulsion adapted to be located most distant from the photographed subject when the emulsion is exposed and preferably also adapted to be most distant from the image-receiving element when in superposed relationship therewith. Placing the dye developer behind the emulsion layer, as in the preferred embodiment, has the advantage of providing increased contrast in the positive image, and also minimizes any light-filtering action by the colored dye developer. In this preferred embodiment, the layer of dye developer may be applied by using a coating solution containing about 0.5 to 8%, by weight, of the dye developer. Similar concentrations may be used if the dye The image-receiving layer receives a depthwise 33 developer is utilized as a component of the liquid processing composition. In an especially useful mode of dispersing the dye developers in the photosensitive elements, the dye developer is dissolved in a water-immiscible solvent and then dispersed in a gelatin coating solution.

The liquid processing composition above referred to comprises at least an aqueous solution of an. alkaline compound, for example, diethylamine, sodium hydroxide or sodium carbonate, and may contain the dye developer.

In some instances, it may contain a minor amount of a conventional developing agent. If the liquid processing composition is to be applied to the emulsion by being spread thereon, preferably in a relatively thin, uniform layer, it may also include a viscosity-increasing compound constituting the film-forming material of the type which, when said composition is spread and dried, will form a relatively firm and relatively stable film. A preferred film-forming material is a high molecular weight polymer such as a polymeric, water-soluble ether inert to an alkali solution, as, for example, a hydroxyethyl cellulose or sodium carboxymethyl cellulose. Other film-forming materials or thickening agents whose .ability to increase viscosity is substantially unaffected when left in solution for a long period of time may also be used.

The novel dye developers of this invention may be represented 'by the formula:

wherein Ar is an aryl radical, preferably a phenyl or naphthyl radical, M is an alkylene radical, n is or 1, Y is an orthoor para-dihydroxyphenyl radical, each of R and R are hydrogen or an aliphatic, e.g., alkyl, hydroxyalkyl radical, andR is a sulfonamido radical. R and R together may be a divalent aliphatic radical, e.g., a pentamethylene radical completing, with the nitrogen atom, a piperidine ring. Preferably R and R together contain no more than 12 to carbons.

In a preferred embodiment, Ar is a phenyl radical, R is hydrogen and R is a hydroxyalkyl radical, Y is a para-dihydroxybenzene radical and n is 1. Such dye developers maybe represented by the formula:

R i i N=NH-HON-alkylene-OH I OH wherein R and M have the same meaning as above.

As examples of alkylene radicals comprehended by the radical M, mention may be made of radicals such as CH --CH I CH,- HCH2 and CH CH CH The preferred embodiment is a lower alkylene group, e.g., less than 6 carbons, and more preferably an ethylene group. It should be understood that M may be an alkylene group comprising 6 or more carbon atoms provided that the resulting dye de- R, mention may be made of:

The length and nature of the alkyl radicals contemplated by R; and R are not critical, however, in preferred embodiments R and R are ethyl groups or isopropyl groups. The sulfonamide radical may be ortho, meta or para to the azo group. In a preferred embodiment, the sulfonamide radical is ortho to the azo group.

The dye developers of this invention are broadly disclosed in the copending application of Milton Green, Serial No. 130,468, filed August 10, 1961, now abandoned in favor of Serial No. 301,197, filed August 9, 1963, and Serial N0. 301,181, filed August 9, 1963, now US. Patent 3,141,772, issued July 21, 1964. The dye developers of this invention are species of the above-mentioned invention and possess advantageous and unexpected properties as a result of the presence of the sulfonamide group on the diazotizable amine over the dye developers which do not possess the sulfonamide group.

The dye developers of this invention have been found to exhibit a still greater degree of control, contrast and stability than that possessed by the yellow dye developers of the above-mentioned copendi-ng application, Serial No. 130,468 and other prior art yellow dye developers such as, for example,

As examples of dye developers within the scope of h i n i n o a 1) ma l t e prese t invent ment1 n m y e de of V SOFIPCSHG GEES (It H CH3 (3H S O2-N- (32H: N=N--*-- O-N C H--C H-C H;

t i 5 u -N=N ""CNCH2CHTCH20H H0 N M N/ HO N (])H I OH CHr-CHa-OH,

Hr'CH I I OH 1 (5) 1 (4' hydroquinonylpropylphenyl)-3-N-(3"a-methyl- 0H fi-hydroxypropyl)-carbamyl 4 [(2" '-N,N-diethylsu1fon- (1) 1-(4-hydroquiu0nylethylphenyl) 3 N ("3" hydroxyammo)phenymz'ol'5'pymzolone propyl) carbamyl 4 [(2"'N,lN-diethylsulfonamido)- C2115 phenylazo 1 -5-pyrazo1one SOz-N-CgHr;

O H E f N=N--- NO H -N N F -NCHz-CH2CHz-OH L H0 S0: 110- \N/ N H3C/N\CH H5 an H3 CH3 I OH OH (I; (kHz-CH: H2-CH I OH OH (6) 1 (4' hydroquinonylethylphenyl)-3-(N-ethy1carbamy1)- (2) 1 (4' hydroquinonylethylphenyl) 3aN-(3-hydroxypro H y )-p y a l-finy a o o fil g g ifi i gig g g 'NlN'dusOpropylsulfonamldo)' 40 The novel dye developers of this invention may be (6 ill prepared by diazotizing an amine of the formula: N=NjlU-CNOHr-CHr-OHg-OH (C) R --NH3 HO Q 1 wherein R has the same meaning as above and coupling fvioz the diazotized compound into a compound of the for- C 2 5NC zH 11111132 OH (I? I --G-0-z CHgCH2 N HO \N/ z ir(M)nY 1 h d 1 1 th 1 h 3 N h d 5 wherein Z is an alkyl radical and Ar, 11 and M have the 1'0 11 nony e y en e y roxypr0- 1 py1) curbam1 i wylgmelhylsulfonamido) pheny1 same meaning as above and Y is the protected derivatlve tazol-Ei-pyrazolone of the orthoor para-dihydroxyphenyl group, preferably $2 5 the acylated derivative thereof; and reacting the thus- SOPN CZH5 formed dye with an amine to form thereby the dye del O H velopers of Formula A. The couplers within Formula g 0 NZN o D are disclosed and claimed in the copendmg application of Milton Green and Phyl is T. Moore, Serial No. H0 130,489, filed August 10, 1961, and now abandoned.

The diazotizable amine,

may be readily prepared by heating a nitrobenzenesulfonyl chloride with the appropriate dial-kyl amine and 7 reducing the resulting compound. It should be noted that the amine to be reacted with the sulfonyl chloride 1 is a secondary amine, since the presence of a hydrogen 0 atom on the sulfonamido nitrogen atom may impart a 1 y q n y pv p eny )-3 -(3- y r0 y-' degree of alkali solubility or difiusibility to the oxidized 7 if employed in diffusion transfer processes, i.e., some of the oxidized dye developer may transfer.

The term acyloxy is intended to signify the grouping D l o wherein D is an aryl, alkyl, aryloxy, or alkoxy group. The terms alkyl and aryl as employed herein are intended to include substituted aryl and alkyl groups, for example, aralkyl and alkaryl groups.

The process of preparing 3-carboxamido pyrazolone dye developers by the replacement of the 3-carboxyl group with the desired amide group is disclosed and claimed in the copending application of Milton Green, Serial No. 130,467, filed August 10, 1961, now abandoned.

The following nonlimiting examples illustrate the preparation of dye developers within the scope of this invention.

Example 1 m-Nitrobenzenesulfonyl chloride, 25 gm., and 200 ml. of diisopropylamine was heated on a steam bath for 24 hours to produce 3-diethylsulfonamido-l-nitrobenzene. The excess amine was boiled ofi and 8 gm. of the product was placed in a Parr shaker with 100 ml. of ethanol and 3 gm. of a 10% palladium/barium sulfate catalyst. Hydrogen uptake was complete in about one hour. The catalyst was removed by filtration and 2.74 ml. of concentrated hydrochloric acid was added to the filtrate and the mixture was then concentrated on the steam bath and anhydrous ether was added to the solution to give a cloudy suspension. To 2.3 gm. of a tan solid which was recov- 'ered was added ml. of concentrated hydrochloric acid and 50 ml. of water. The solution was cooled to about 0 to 5 C. and a solution of 0.54 gm. of sodium nitrite was added. The solution was stirred for 2 hours at a temperature of about 0 to 5 C., then filtered and added dropwise to a stirred mixture of 3.4 gm. of l-(p-[2',5'- diacetoxyphenylethyl]-phenyl) 3 carbethoxy-S-pyrazolone, an excess of sodium bicarbonate, 150 ml. of acetone and 100 ml. of water. Stirring was continued overnight. An oil separated and solidified. The solid was filtered, washed with water and sucked dry. To a deaerated solution of 50 ml. of 3-amino-1-pr0pano1 and 50 ml. of ethanol was added 4.4 gm. of the solid dye. The mixture was then heated for two hours on the steambath in a nitrogen atmosphere. The mixture was cooled and poured into a beaker containing an excess of hydrochloric acid and ice. 1-(4-hydroquinonylethylphenyl) 3 N (3"- hydroxypropyl)-carbamyl 4 [('2'"-N,N-diisopropylsulfonamido)-phenylazo]-5-pyrazolone was filtered, washed with water, sucked dry and recrystallized from ethanol. The product melted at 215218 C.

Exam p le 2 1-(4'-hydroquinonylethylphenyl) 3 N-(3-hydroxypropyl)-carbamyl 4 [(2 N,N-diethylsulfonamido)- phenylazo]-5-pyrazolone, melting at 138-140 C., was prepared according to the procedure of Example 1 by diazotizing and coupling o'-amino N,N diethylbenzenesulfonamide into 1 (p [2,5' diacetoxyphenylethyl} 'phenyl)-3-carbethoxy-5-pyrazolone and treating the resulting product with 3-amino-1-propanol in a nitrogen atmosphere.

Example 3 Example 4 1-(4'-hydroquinonylpropylphenyl)-3-N-(3 hydroxypropyl)-carbamyl 4 [(2' N,N-diethylsulfonamido)- phenylazo]-5-pyrazolone was prepared according to the procedure of Example 1 by diazotizing and coupling 0- amino-N,N-diethylbenzenesulfonamide into 1-(p-[2',5- diacetoxyphenylpropyl] phenyl)-3-carbethoxy-5-pyrazolone and treating the resulting product with 3-amino-1- propanol in a nitrogen atmosphere.

Example 5 1-(4-hydroquinonylpropylphenyl) 3-N-(3"-u-methyl- /3-hydroxypropyl)-carbamyl 4 [(2 N,N-diethylsulfonamido)phenylazo]-5-pyrazolone was prepared according to the procedure of Example 1 by diazotizing and coupling o-amino-N,N-diethylbenzenesulfonamide into 1- (p- 2',5 '-diacetoxyphenylpropyl] -phenyl) -3 carbethoxy- S-pyrazolone and treating the resulting product with 2- amino-3-butan0l in a nitrogen atmosphere.

The following examples of the photographic utilization of the dye developers of this invention are given for the purposes of illustration only.

Example 6 A photosensitive'element was prepared by coating a gelatin subcoated film base with a solution comprising 0.089 gm. of 1-(4'-hydroquinonylethylphenyl)-3-N-(3"- hydroxypropyl)-carbamyl 4 [(2"-N,N-diethylsulfonamido)-phenylazo]-5-pyrazolone dissolved in 10 cc. of a solution of 2% cellulose acetate hydrogen phthalate in distilled tetrahydrofuran. After this coating dried, a blue-sensitive silver iodobromide emulsion was applied and allowed to dry. This photosensitive element was exposed, and brought into superposed relationship with an image-receiving element as an aqueous liquid composition comprising:

Water cc 100.00

NaOH gm 5.17

Hydroxyethyl cellulose (high viscosity) [commercially available from Hercules Powder Co., Wilmington 99, Delaware, under the trade name Natrasol 250] gm 4.03 Sodium thiosulfate gm 1.15 Benzotriazole gm 2.3 N-benzyl-u-picolinium bromide gm 2.3

was spread between said elements. The image-receiving element comprised a 2:1 mixture, by weight, of polyvinyl alcohol and poly-4-vinylpyridine on a baryta paper sup-. port. After an imbibition period of approximately 1 minute, the image-receiving element was separated and contained a yellow positive image.

Example 7 The procedure described irrExample 6 was repeated, except that the dye developer was dispersed in a layer of gelatin. The coating solution from which the dye developer layer was coated was prepared by adding 0.5 gm. of the dye developer dissolved in 1 cc. of N-n butyI- acetanilide and 0.5 cc. of cyclohexanone to 5 gm. of 10% gelatin solution, 1.67 cc. of water, and 0.67 cc. of Alk-anol B. Emulsification was effected by high speed agitation in a Waring Blendor. 5 cc. of the resulting dye dispersion was added to 10 cc. of water containing small amounts of saponin and succinaldehyde, and then coated on the gelatin-subcoated cellulose acetate film base.

Substitution of the other dye developers described above in the procedures described in Examples 6 and 7 gave similar positive transfer images.

In order to illustrate the above-mentioned increased stability of the dye developers of this invention, a comparison of results of an accelerated fading test was made.

xenon are along with yellow positive images prepared according to the procedure of Example. 6 but using (A) 1 phenyl 3-N-n-hexylcarbamyl-4-[p-(2,5'-dihydroxyphenethyl)'-phenylazo]-5-parazolone in one instance and (B) 1 hydroquinonylethylphenyl-3-N,N-diethylcarbamyl 4 (2,4,6'-trimethylphenylazo)-5-pyrazolone in another instance. The positive image of Example 6 was designated (C). The table below sets forth the per cent fading after swabbing the prints with a boric acid solution followed by exposure to the xenon are for 40 and 100 hours. The integral densities of the images were measured prior to the test and after exposure to the It should also be noted that the dye developers of this invention fade to a true yellow color. In other words, a color change is not involved as a result of the fading of the image, just a diminishing of the intensity of the same color.

The novel dye developers of this invention are also suitable for use with liquid processing compositions which contain cesium hydroxide, which are disclosed and claimed in the copend-ing application of George H. Fernald, Jr., Serial No. 247,867, filed December 2 8, 1962, and compositions which contain potassium hydroxide, which are disclosed and claimed in the copending application of Dorothy C. Mendelsohn, Serial No. 247,863, filed December 28, 1962.

The novel dye developers of this invention are also suitable for use with image-receiving elements containing a layer of a polymeric acid between the image-receiving layer and the support and prepared in accordance with the invention disclosed and claimed in the copending application of Edwin H. Land, Serial No. 234,864, filed November 1, 1962.

The dye developers of this invention are also useful in integral multilayer photosensitive elements for use in multicolor diffusion transfer processes. As an example of such photosensitive elements, mention may be made of the photosensitive elements disclosed and claimed in the copending US. application of Edwin H. Land and Howard G. Rogers, Serial No. 565,135, filed February 13, 1956, wherein at least two selectively sensitized photosensitive strata are superposed on a single support and are processed, simultaneously and without separation, with a single common image-receiving element. A suitable arrangement of this type comprises .a supportcarrying a red-sensitive silver halide emulsion stratum, a green-sensitive silver halide emulsion stratum and a blue-sensitive silver halide emulsion stratum, said emuls-ions having associated therewith, respectively, a cyan dye developer, a magenta dye developer and a yellow dye developer. In one of the preferred embodiments of photosensitive elements of this type, the dye developers are disposed in separate alkali-permeable layers behind the photosensitive silver halide emulsion stratum with which they are associated.

The photosensitive elements within the scope of this invention may be used in roll film units which contain a plurality of photosensitive frames. The photosensitive elements of this invention are especially useful in composite roll film intended for use in a Polaroid Land Camera or a similar camera structure such, for example, as the camera forming the subject matter of US. Patent No. 2,435,717, issued to Edwin H. Land on February 10, 1948. In general, such composite roll films comprise a photosensitive roll, a roll of imagereceiving material and a plurality of pods containing an aqueous. alkaline processing solution. The rolls and pods are so associated with each other that, upon processing, the photosensitive element may be superposed on the image-receiving element and the pods may be ruptured to spread the aqueous alkaline processing solution between the superposed elements. The nature and construction of the pods used in such units are well known to the art. See, for example, US. Patents Nos. 2,543,- 181 and 2,634,886, issued to Edwin H. Land.

It will be noted that the liquid processing composition may contain one or more auxiliary or accelerating silver halide developing agents, such as p-methylaminophenol (Metol); 2,4-diaminophenol (Amidol); benzylaminophenyl; hydroquinone; a substituted hydroquinone such as toluhydroquinone, phenylhydnoquinone, or 4'-methylphenylhydroquinone; or a 3-pyrazolidone such as 1- phenyl-3apyrazolidone. These silver halide developing agents are substantially colorless, at least in their unoxidized form. It is possible that some of the dye devel-oper oxidized in exposed areas may be oxidized by an energy transfer reaction with oxidized auxiliary developing agent.

In addition, development may be effected in the pres ence of an onium compound, particularly. a quaternary ammonium compound, in accordance with the processes disclosed and claimed in the copending US. application of Milton Green and Howard G. Rogers, Serial No. 50,851, filed August 22, 1960, and now U.S. Patent 3,- 173,786.

The dye developers of this invention may be used also in conventional photographic processes, such as tray or tank development of conventional photosensitive films, plates or papers to obtain black and white, monochromatic or toned prints or negatives. By way of example, a developer composition suitable for such use may comprise an aqueous solution of approximately 12% of the dye developer, 1% sodium hydroxide, 2% sodium sulfite and 0.05% potassium bromide. After development is completed, any unreacted dye developer is washed out of the photosensitive element, preferably with an alkaline washing medium or other medium in which the unreacted dye developer is soluble. The expression toned is used to designate photographic images wherein the silver is retained with the precipitated dye, whereas monochromatic is intended to designate dye images free of silver.

It should be noted that the dye developers of this medium are self-sufficient to provide the desired color image and do not depend upon coupling reactions to produce the desired color. They thus provide a complete departure from conventional photographic color processes in which the color is produced by a coupling reaction between a color former or coupler and the oxidized developing agent, as well as so-called auto-coupling processes in which color is obtained by a reaction of the oxidized developing agent with unoxidized developing agent.

It will be apparent that, by appropriate selection of the image-receiving element from among suitable known opaque and transparent materials, it is possible to obtain either a colored positive reflection print or a colored positive transparency. Likewise, the inventive concepts herein set forth are adaptable for multicolor work by the use of special photographic materials, for example, film materials of the type containing two or more photosensitized elements associated with an appropriate number of image-receiving elements and adapted to be treated with one or more liquid processing compositions, appropriate dye developers suitable to impart the desired subtractive colors being incorporated in the photosensitized elements or in the liquid processing compositions. Examples of such photographic materials are disclosed in US. Patent No. 2,647,049 to Edwin H. Land.

As examples of useful image-receiving materials, menion may be made of nylon, e.g., N-methoxymethyl-polyhexamethylene adipamide, polyvinyl alcohol, and gelatin, particularly polyvinyl alcohol or gelatin containing a dye mordant such as poly-4-vinylpyridine. The image-receiving element also may contain a development restrainer, e.g., l-phenyl-5-mercaptotetrazole, as disclosed in the copending application of Howard G. Rogers and Harrie-t W. Lutes, Serial No. 50,849, filed August 22, 1960.

The inventive concepts herein set forth are also adaptable for the formation of colored images in accordance with the photographic products and processes described and claimed in US. Patent No. 2,968,559, issued to Edwin H. Land on January 17, 1961.

The novel compounds herein disclosed are also suitable for use as dyes for textile fibres, such as nylon. In the preceding portions of the specification the expression color has been frequently used. This expression is intended to include the use of a plurality of colors to obtain black.

7 Since certain changes may be made in the above products, compositions and processes without departing from the scope of the invention herein involved, it is intended that all matter contained in the above description shall be interpreted as illustrative and not in a limiting sense.

What is claimed is:

1. A compound of the formula:

wherein each of R and R are lower alkyl radicals, each of R and R is a radical selected from the group consisting of hydrogen, lower hydroxyalkyl and lower alkyl radicals and R and R taken together may be a pentamethylene radical completing, with the nitrogen atom attached thereto, a piperidine ring, Ar is an aryl radical, selected from the group consisting of phenyl and naphthyl radicals, M is a lower alkylene radical, n is an integer from 0 to 1, inclusive, and Y is para-dihydroxyphenyl radical.

, 2. 1- (4-hydroquinonylethylphenyl)-3-N-(3"-hydroxypropyl)-carbamyl 4 [(2 N,N diethyl-sulfonamido)- phenylazo1-5-pyrazolone.

3. 1-(4-hydroquinonylethylphenyl) 3-N-(3"-hydroxypropyl) -carbamyl-4-[ 2"'-N,N-diisopropylsulfonamido) phenylazo1-5-pyrazolone.

4. 1 (4' hydroquinonylethylphenyl)-3-N-3"-hydroxypropyl)-carbamyl-4-[(3" N,N diethylsulfonamido)- phenylazoJ-S-pyrazolone.

4. 1-(4-hydroquinonylethylphenyl) 3-N-(3"-.hydroxyhydroxypropyl) canbamyl 4 [(2"'-N,N-diethylsulfonamido)-phenylazo]-5-pyrazolone.

6. 1-(4' hydroquinonylpropylphenyl) 3 N (3' 0;- methyl-fi-hydroxypropyl) carbamyl-4-[(2"'-N,N-diethylsulfonamido)-phenylazo]-5-pyrazolone.

7. 1 (4 hydroquinonylethylphenyl)-3-(N-ethylcarbamyl)-4-[(2"-N,N-diethylsulfonamido) phenylazo1- 5-pyrazolone.

No references cited.

CHARLES B. PARKER, Primary Examiner.

R. J. FINNEGAN, FLOYD D. HIGEL,

Assistant Examiners.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,275,617 September 27, 1966 Milton Green It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

In the heading to the printed specification, line 3, for

"(HYDROXYLALKYL) read (HYDROXYALKYL) column 9, line 4, for "parazolone" read pyrazolone line 55, for "support-" read support column 12, line 9, after "is" insert a line 17, for "-3" read )3 line 20, for

"4. 1-(4hydroquinonylethylphenyl)-3N(3 -hydroxy" read 5. l [4hydroquinonylpropylphenyl) 3-N- (3 Signed and sealed this 29th day of August 1967.

( AL) Attest:

ERNEST W. SWIDER EDWARD-J. BRENNER Attesting Officer Commissioner of Patents 

1. A COMPOUND OF THE FORMULA: 